Answer:
If Earth's axis was not tilted then the climate zones would change, there would be no seasons, and the day and night will last the same all year.
Explanation:
Earth's axis is tilted, and with it circling around the Sun, there a great effects on the planet's surface, from climate, duration of day and night throughout the year, change of seasons, amount of sunlight, etc. But if this was to change and Earth's axis is not tilted, then there will changes in pretty much everything on Earth's surface.
The climate zones will be very clearly separated by latitude, and every climate zone will be more or less monotonous throughout the year, with just minimal changes every now and then. This will happen because the amount of sunlight and the angle under which the sunlight falls will the same at a given place throughout all of the year. The day and night will also be the same, unlike the changes they experience with the tilted axis. To put it simply, the equatorial area will remain pretty much the same, but if we take the temperate zones then they will experience climate like it is always spring or autumn, while the higher latitudes will constantly be frozen and experience winter.
